U.S. Pat. No. 3,693,846 discloses utilizing arms extending transversely in opposite directions from the discharge conduit end cap bails, to insure that the operating shafts for longitudinally spaced outlet valve elements in the outlet are in the closed position when the end cap is applied to the discharge tube. U.S. Pat. No. 3,980,212 discloses an angle mounted upon the discharge conduit end wall adapted to engage discs mounted on operating handles to prevent the operating handles from moving out of the stored position while the outlet is in transit. These arrangements increase the cost of the end cap and/or the cost of the end cap ball.
In U.S. Pat. No. 4,114,785 issued Sept. 19, 1978 assigned to the same assignee as the present application, a protrusion is formed on the upper inner edge of the end cap. When the end cap is applied, the operating handles obstruct the path of the protrusion unless the valve elements and operating handles are in the fully closed position.